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91.
[目的]研究真武汤合苓桂术甘汤对心肾综合征大鼠模型水钠潴留的作用机制。[方法]将60只雄性SD大鼠随机分为两组,即空白组与手术组,空白组大鼠常规饲养,手术组大鼠经5/6肾切除联合异丙肾上腺素皮下注射制备心肾综合征模型,剔除死亡大鼠后,将手术组剩余成模大鼠按体质量分层随机分为空白组、中药组、常规治疗组。中药组给予真武汤合苓桂术甘汤灌胃,给药量为7.29 g生药/(kg·d);常规治疗组给予贝那普利(0.45 mg/kg)+呋塞米(1.8m g/kg);空白组予以等容积生理盐水灌胃,每日1次,连续6周。观察实验过程中各组大鼠的精神状态、活动情况、灵敏度、毛发情况、食欲、大小便等一般情况及死亡情况,比较各组灌胃前、灌胃6周后的血清脑钠肽(BNP)、血肌酐(Scr)、血尿素氮(BUN)、尿水通道蛋白2(AQP2)的前后差值情况。[结果]灌胃6周后,中药组大鼠一般情况较灌胃前改善、喘息不明显,常规治疗组一般情况同样较灌胃前改善。通过比较治疗前后各组大鼠实验室指标差值发现,中药组与常规治疗组BNP均下降,中药改善大鼠心力衰竭情况接近常规治疗组水平,两组下降水平无统计学差异(P0.05);中药组Scr水平较前下降,常规治疗组Scr水平升高;中药组尿AQP2水平较前略增高,与空白组尿AQP2水平无统计学差异(P0.05),常规治疗组尿AQP2水平较前明显升高。[结论]心肾综合征大鼠尿AQP2的表达主要由肾脏调控,AQP2可作为心肾综合征水钠潴留状态的参考指标,真武汤合苓桂术甘汤改善心肾综合征大鼠水钠潴留状态的作用机制可能是通过抑制大鼠肾脏AQP2过度表达,减少水的重吸收,改善了水钠潴留状态。  相似文献   
92.
目的:评估八段锦干预心力衰竭的疗效及安全性。方法:搜索中国知网数据库、中国生物医学文献数据库、万方数据库以及维普中文全文数据库;PubMed、Cochrane Library、web of science、EMBASE。检索时间为建库至2019年2月28日。对纳入的随机对照试验(RCT)用Cochrane手册进行偏倚风险评估,用Rev Man 5.3软件进行Meta分析。结果:纳入6篇文献,7个随机对照研究,共计543例心力衰竭患者。与对照组比较,观察组MLHFQ减少[MD=10.88,95%CI=(8.22,13.54)],6分钟步行试验(6MWT)提高[MD=107.81,95%CI=(75.83,139.78)],左心室射血分数(LVEF)提高[MD=3.62,95%CI=(2.04,5.19)],B型利钠肽(BNP)降低[MD=73.32,95%CI=(45.12,101.53)],临床疗效[OR=4.00,95%CI=(1.35,11.83)],中医证候评分[OR=4.57,95%CI=(2.03,10.31)]。结论:八段锦可改善心力衰竭患者的心功能,用于稳定期的康复治疗。  相似文献   
93.
目的研究丹蛭降糖胶囊对糖尿病肾病大鼠的肾脏病理改变和足细胞自噬水平的影响,初步探讨其相应的作用机制。方法选取GK大鼠40只,采用醋酸脱氧皮质酮-盐皮下注射联合高脂饲料喂养诱导糖尿病肾病模型。造模成功后随机分为模型组、丹蛭降糖胶囊低剂量组[0.54 g/(kg·d)]、高剂量组[1.08 g/(kg·d)]、缬沙坦组[10 mg/(kg·d)],每组10只。另选取10只同周龄正常Wistar大鼠作为正常组。模型组和正常组给予等容积生理盐水。连续灌胃10周后检测空腹血糖(FBG)、血肌酐(SCr)、尿素氮(BUN)和尿微量蛋白(U-mAlb)。Western Blot检测肾小球p-mTOR、p-S6K1、Beclin-1、LC3和Nephrin蛋白的表达,HE染色和PAS染色后于光镜下观察肾脏病理变化,电镜下观察各组亚细胞形态结构变化。结果与正常组比较,模型组FBG、SCr、BUN、U-mAlb水平升高(P<0.01);与模型组比较,丹蛭降糖胶囊低、高剂量组和缬沙坦组U-mAlb水平降低(P<0.01)。模型组可见肾小球基底膜增厚,系膜基质沉积,足细胞损伤,各用药组均有不同程度改善,丹蛭降糖胶囊高剂量组足细胞内有较多自噬体形成。与正常组比较,模型组p-mTOR、p-S6K1的表达增高,Nephrin、Beclin-1和LC3的表达水平降低(P<0.01);与模型组比较,各用药组p-mTOR、p-S6K1的表达下降,Nephrin、Beclin-1和LC3的表达增高(P<0.01)。丹蛭降糖胶囊高剂量组和缬沙坦组Beclin1、LC3Ⅱ/LC3Ⅰ水平较丹蛭降糖胶囊低剂量组升高(P<0.05)。结论丹蛭降糖胶囊具有减轻糖尿病肾病大鼠U-mAIb、足细胞损伤及相关肾脏病理改变的作用,其机制可能与抑制mTOR/S6K1信号通路进而提高足细胞的自噬活性有关。  相似文献   
94.
ObjectivesCerebral microbleeds (CMBs), which can be detected by gradient-echo T2*-weighted magnetic resonance imaging (MRI), represent small chronic brain hemorrhages caused by structural abnormalities in cerebral small vessels. CMBs are known to be a potential predictor of future stroke, and are associated with age, various cardiovascular risk factors, cognitive impairment, and the use of antithrombotic drugs. Patients with coronary artery disease (CAD) are at potentially high risk of CMBs due to the presence of coexistent conditions. However, little is known about CMBs in patients with CAD. We aimed to identify the factors associated with the presence of CMBs among patients with CAD.MethodsWe evaluated 356 consecutive patients [mean age, 72 ± 10 years; men = 276 (78%)] with angiographically proven CAD who underwent T2*-weighted brain MRI. The brain MRI was assessed by researchers blinded to the patients’ clinical details.ResultsCMBs were found in 128 (36%) patients. Among 356 patients, 119 (33%) had previously undergone percutaneous coronary intervention (PCI), and 26 (7%) coronary artery bypass grafting (CABG). There was no significant relationship between CMBs and sex, hypertension, dyslipidemia, diabetes mellitus, anticoagulation therapy, antiplatelet therapy, or prior PCI. CMBs were significantly associated with advanced age, previous CABG, eGFR, non-HDL cholesterol, carotid artery disease, long-term antiplatelet therapy, and long-term dual antiplatelet therapy (DAPT) using univariate logistic regression analysis. The multivariate logistic regression analysis showed that long-term antiplatelet therapy (odds ratio, 1.73; 95% CI, 1.06 – 2.84; P = 0.03) or long-term DAPT (odds ratio, 2.92; 95% CI, 1.39 – 6.17; P = 0.004) was significantly associated with CMBs after adjustment for confounding variables.ConclusionsCMBs were frequently observed in patients with CAD and were significantly associated with long-term antiplatelet therapy, especially long-term DAPT.  相似文献   
95.
受体酪氨酸激酶(RTKs)是一种主要的膜受体,调控细胞增殖、分化和迁移。解除RTK信号通路的管制会导致许多疾病,如癌症和发育障碍。促红细胞生成素肝细胞受体(Erythropoietin-producing hepatocellular,Eph)家族是酪氨酸激酶受体家族中最大的一个亚族,其与配体Ephrin的相互作用在生长发育和肿瘤发生过程中发挥着重要作用。研究表明,一种缺乏酪氨酸激酶活性的特殊Eph受体EphB6在乳腺癌、结直肠癌等许多恶性肿瘤中表达下降,而大量证据表明EphB6表达的缺失依赖于其启动子DNA的高甲基化,进而促进肿瘤的进展与转移。EphB6是近期研究的热点因子,本文就其目前在恶性肿瘤中研究进展做一综述。  相似文献   
96.
《Cancer radiothérapie》2020,24(3):199-205
PurposeA high level of accuracy while positioning the patient is mandatory for frameless stereotactic radiotherapy (SRT), as large doses in multiple fractions can be delivered near organs at risk. The objective of this study is to propose an end-to-end quality assurance method to verify that submillimetre alignment can be achieved with stereotactic conventional linacs.MethodsWe used a TrueBeam® linear accelerator equipped with a 6DOF robotic couch. The “ISO Cube” phantom was used with a homemade stand designed to generate known translational and rotational offsets. A reference CT scan was performed with straight alignment of the phantom. The procedure introduced 1.6° angular offset for the couch pitch and roll, at various gantry angles. The couch base was also moved between 0° and 270°. We compared the results with the daily machine performance check tests (MPC, Varian).ResultsThe mean isocentre size, MV and kV imager offsets were found to agree to within 0.1 mm, 0.1 mm and 0.3 mm respectively, and were in close agreement between the methods. For a total four months data collection period, the mean deviation between requested and measured 6DOF couch shifts was 0.6 mm and 0.2°. Errors on field size were smaller than 1 mm for 97.7% of the 324 data points.ConclusionResults demonstrate that the linac equipped with a 6DOF robotic positioner and CBCT imaging satisfies requirements for SRT. Our methodology, based on a modified Winston-Lutz quality control, allowed us to quantitatively assess end-to-end accuracy of a linac in order to safely deliver SRT.  相似文献   
97.
PurposeExaggerated release of proinflammatory mediators during sepsis contributes to inadequate vasodilatation and depressed myocardial contractility, which lead to development of shock and circulatory collapse. The aim of the study was to evaluate the effect of IL-6 and aging on activation of intracellular signaling pathways in the myocardium induced by bacterial lipopolysaccharide (LPS) administration.Material/methodsLPS was injected intraperitoneally to male 3- and 24-month old mice with systemic IL-6 gene knock-out (IL-6KO) and the reference strain (WT). LPS was given intraperitoneally in single low (0.1 mg/kg) or high (10 mg/kg) dose, or in two doses (0.1 + 10 mg/kg) with 24-h delay. The expression and phosphorylation of STAT3, ERK1/2, Akt1/2/3 proteins in the left ventricular myocardium was evaluated after 24 h using Western blotting.ResultsLow LPS dose induced higher STAT3 phosphorylation only in old IL-6KO mice, not affecting ERK1/2 and Akt1/2/3 phosphorylation in any group. High LPS dose upregulated STAT3 phosphorylation similarly in all groups, reduced ERK1/2 expression in young WT mice and upregulated Akt1/2/3 expression and phosphorylation in young IL-6KO mice. Pretreatment with low LPS dose attenuated phosphorylation of STAT3 in both old groups and phosphorylation of Akt1/2/3 in young IL-6KO group. Two-dose approach also significantly potentiated ERK1/2 phosphorylation in both old groups.ConclusionsObtained results show that IL-6 deficiency alters the activity of intracellular signaling pathways: JAK/STAT in old and Akt in young LPS-treated mice. This may indicate that lack of IL-6 attenuates Akt-related cytoprotective effect of pretreatment with low LPS dose in young but not in aged animals.  相似文献   
98.
目的:观察脂多糖(lipopolysaccharide,LPS)诱导肺成纤维细胞及肺组织有氧糖酵解关键酶6-磷酸果糖-2-激酶/果糖-2,6-二磷酸酶3(6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3,PFKFB3)表达及其与有氧糖酵解的关系,探讨在LPS诱导肺纤维化过程中肺成纤维细胞和肺组织有氧糖酵解的潜在机制。方法:将人胚肺成纤维细胞MRC-5细胞系采用随机数字表法分为PBS对照组(PBS组)和LPS组(每组3孔),Western blot检测LPS刺激细胞6h后PFKFB3表达情况,同时免疫荧光显示PFKFB3在细胞内的定位情况;于LPS刺激后48 h采用海马细胞能量代谢仪检测细胞耗氧率(oxygen consumption rate,OCR)和产酸率(extracellular acidification rate,ECAR),并采用比色法检测有氧糖酵解产物乳酸产生情况,同时Western blot检测LPS刺激48 h后Ⅰ型胶原蛋白合成情况。将24只C57BL/6小鼠按随机数字表法分为生理盐水对照组(C组)、LPS组(L组),每组12只,L组、C组连续5d分别腹腔注射5 mg/kg LPS、等容量生理盐水;每组各6只于造模后第7天无痛处死小鼠,取血浆和肺组织,Western blot和免疫荧光检测各组肺组织中PFKFB3表达情况,比色法检测各组小鼠血浆中乳酸的含量;剩余小鼠于造模后第28天取肺组织,一侧肺通过Western blot检测肺组织Ⅰ型胶原蛋白合成情况,另一侧肺做石蜡切片进行病理学检测。结果:与PBS组比较,LPS刺激细胞6h后PFKFB3表达明显升高(P<0.05);LPS刺激细胞48 h后,与PBS组比较,LPS组细胞耗氧率降低、产酸率增加,代谢产物乳酸含量明显升高(P<0.05),同时细胞Ⅰ型胶原蛋白合成显著增加(P<0.05)。与C组比较,L组小鼠腹腔注射LPS 7 d后肺组织中PFKFB3表达明显升高(P<0.05),血浆乳酸含量明显升高(P<0.05);LPS注射28 d后,L组小鼠Ⅰ型胶原蛋白表达明显升高(P<0.05),肺组织出现明显纤维化。结论:在LPS诱导的肺纤维化过程中,LPS可诱导肺成纤维细胞和肺组织中PFKFB3蛋白表达,该过程与其有氧糖酵解过程相关,PFKFB3的表达上调可能是LPS诱导肺成纤维细胞和肺组织有氧糖酵解和肺纤维化的关键环节。  相似文献   
99.
王焓  段萍 《温州医科大学学报》2022,52(3):180-185,193
目的:探讨脂肪和肥胖相关基因(FTO)对异位子宫内膜间质细胞(eESCs)纤维化的影响及其机制。方法:采用实时定量聚合酶链反应(qRT-PCR)检测子宫内膜异位症(EMs)患者病变组织中m6A相关基因的表达;通过慢病毒载体过表达FTO,在eESCs中检测纤维化相关基因的表达;通过m6A2 Target数据库和MeRIP-qPCR预测和验证eESCs中FTO与Toll样受体2(TLR2)的关系;Western blot法检测p38的蛋白表达变化。结果:FTO在EMs中表达下调(P <0.05);FTO过表达促进eESCs纤维化并抑制其增殖(P <0.05);在eESCs中,FTO通过TLR2 的m6A修饰途径上调其蛋白水平(P <0.05);FTO在eESCs中经TLR2/p38 信号通路促进细胞纤维化(P <0.05)。结论:FTO在EMs中低表达,上调FTO可能通过TLR2/p38信号通路促进eESCs纤维化。  相似文献   
100.
Background: Primary studies have shown that the IL-12B rs3212227 and IL-6 rs1800795 polymorphisms are associated with an increased risk of cervical cancer. However, conflicting results warrant a meta-analysis to obtain more precise estimates. Methods: A comprehensive literate search on PubMed, Web of Science, Scopus, CNKI, and SciELO was performed to collect all eligible studies up to November 10, 2019. The pooled odds ratios (OR) and 95% confidence intervals (CI) were used to calculate the risk. This meta-analysis was carried out by utilizing CMA software. Results: A total of eleven case-control studies including four studies on IL-12B rs3212227 and seven studies on IL-6 rs1800795 were selected. Pooled ORs revealed that the IL-6 rs1800795 polymorphism was significantly associated with an increased risk of cervical cancer (C vs. G: OR = 1.294, 95% CI 1.071-1.564, p= 0.007; CC vs. GG: OR = 1.633, 95% CI 1.059-2.520, p= 0.027; CC+CG vs. GG: OR = 1.312, 95% CI 1.048-1.643, p= 0.018; and CC vs. CG+GG: OR = 1.592, 95% CI 1.268-1.999, p≤0.001), but not IL-12B rs3212227 polymorphism. Stratified analysis by ethnicity revealed that both IL-12B rs3212227 and IL-6 rs1800795 polymorphisms were associated with risk of cervical cancer in Asian women. Conclusions: Our pooled data revealed that the IL-12B rs3212227 and IL-6 rs1800795 polymorphisms may be used to identify individuals at high risk of cervical cancer in Asian women.  相似文献   
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